Twisted pair cables are commonly used in the telecommunications industry to transmit data or other types of telecommunications signals. A typical twisted pair cable includes a plurality of twisted wire pairs enclosed within an outer jacket. Each twisted wire pair includes wires that are twisted together at a predetermined lay length. Each wire includes an electrical conductor made of a material such as copper, and a dielectric insulator surrounding the electrical conductor.
The telecommunication industry is driven to provide telecommunication cables capable of accommodating wider ranges of signal frequencies and increased bandwidth. To improve performance in a twisted wire pair, it is desirable to lower the dielectric constant (DK) of the insulator surrounding each electrical conductor of the twisted pair. As disclosed in U.S. Pat. No. 7,049,519, which is hereby incorporated by reference, the insulators of the twisted pairs can be provided with air channels. Because air has a DK value of 1, the air channels lower the effective DK value of the insulators thereby providing improved performance.
Providing an insulator with increased air content lowers the effective DK value of the insulator. However, the addition of too much air to the insulator can cause the insulator to have poor mechanical/physical properties. For example, if too much air is present in an insulator, the insulator may be prone to crushing. Thus, effective twisted pair cable design involves a constant balance between insulator DK value and insulator physical properties